Camera imaging method, camera system and unmanned aerial vehicle (uav)

ABSTRACT

The present invention discloses a camera imaging method, a camera system and an unmanned aerial vehicle (UAV). The camera imaging method is applied to a camera system of the UAV. The camera system includes a signal trigger device and a signal receiving device. The method includes: acquiring, by the signal trigger device, a shooting instruction;generating, by the signal trigger device, a trigger signal with a preset trigger frame rate according to the shooting instruction; and performing, by the signal receiving device, exposure at the preset trigger frame rate according to the trigger signal; where the preset trigger frame rate is greater than a default exposure frame rate of the signal receiving device. According to the present invention, an exposure frame rate of the signal receiving device is adjusted to the preset trigger frame rate, so that the signal receiving device can perform exposure according to the preset trigger frame rate, and synchronous dual-light exposure is implemented.

BACKGROUND Cross Reference

This application is a continuation of U.S. patent application Ser. No.17/081,207 filed on Oct. 27, 2020, all of which are incorporated hereinby reference in their entireties.

Technical Field

The present invention relates to the field of an unmanned aerial vehicle(UAV), and in particular, to a camera imaging method, a camera systemand an unmanned aerial vehicle.

Related Art

At present, an important use of an industrial UAV is aerialreconnaissance. A payload of such UAV generally carries a camera systemthat combines a combination of visible light and infrared thermalimaging. Such dual light is fused together for output. If the dual lightis not exposed synchronously, a smear or tandem phenomenon will occur ona picture, affecting a shooting effect.

SUMMARY

In order to overcome a problem of unsynchronized dual-light exposure ofan aerial camera in the prior art, the present invention is intended toprovide a camera imaging method, a camera system and an unmanned aerialvehicle (UAV).

The present invention provides a camera imaging method applied to acamera system of the UAV. The camera system includes a signal triggerdevice and a signal receiving device. The method includes:

acquiring, by the signal trigger device, a shooting instruction;

generating, by the signal trigger device, a trigger signal with a presettrigger frame rate according to the shooting instruction; and

performing, by the signal receiving device, exposure at the presettrigger frame rate according to the trigger signal; where the presettrigger frame rate is greater than a default exposure frame rate of thesignal receiving device.

In an embodiment of the present invention, the signal trigger device isa first imaging device, and the signal receiving device is a secondimaging device, the preset trigger frame rate being a default exposureframe rate of the first imaging device, the default exposure frame rateof the first imaging device being greater than a default exposure framerate of the second imaging device; and

the performing, by the signal receiving device, exposure at the presettrigger frame rate according to the trigger signal includes:

performing, by the second imaging device, exposure at the defaultexposure frame rate of the first imaging device according to the triggersignal.

In an embodiment of the present invention, the method further includes:

fusing an image produced by the first imaging device at its defaultexposure frame rate with an image produced by the second imaging devicethrough exposure at the default exposure frame rate of the first imagingdevice.

In an embodiment of the present invention, the signal trigger device isa main processor, and the signal receiving device is a first imagingdevice and a second imaging device, the preset trigger frame rate beinga trigger frame rate of the main processor, the trigger frame rate ofthe main processor being greater than the default exposure frame rate ofthe first imaging device and a default exposure frame rate of the secondimaging device, and

the performing, by the signal receiving device, exposure at the presettrigger frame rate according to the trigger signal includes:

performing, by the first imaging device and the second imaging device,exposure at the trigger frame rate of the main processor according tothe trigger signal.

In an embodiment of the present invention, the method further includes:

fusing an image produced by the first imaging device through exposure atthe trigger frame rate of the main processor with an image produced bythe second imaging device through exposure at the trigger frame rate ofthe main processor.

In an embodiment of the present invention, the first imaging device is avisible light imaging lens, and the second imaging device is an infraredimaging lens.

In an embodiment of the present invention, the first imaging device isan infrared imaging lens, and the second imaging device is a visiblelight imaging lens.

In an embodiment of the present invention, the method further includes:

performing zooming on an image produced through exposure of the visiblelight lens.

The present invention further provides a camera system, the camerasystem including a signal trigger device and a signal receiving device;where the signal trigger device is configured to acquire a shootinginstruction; and generate a trigger signal with a preset trigger framerate according to the shooting instruction; and

the signal receiving device is configured to perform exposure at thepreset trigger frame rate according to the trigger signal, where thepreset trigger frame rate is greater than a default exposure frame rateof the signal receiving device.

In an embodiment of the present invention, the signal trigger device isa first imaging device, and the signal receiving device is a secondimaging device, the preset trigger frame rate being a default exposureframe rate of the first imaging device, the default exposure frame rateof the first imaging device being greater than a default exposure framerate of a second imaging device.

In an embodiment of the present invention, the signal trigger device isa main processor, and the signal receiving device is a first imagingdevice and a second imaging device, the preset trigger frame rate beinga trigger frame rate of the main processor, the trigger frame rate ofthe main processor being greater than the default exposure frame rate ofthe first imaging device and the default exposure frame rate of thesecond imaging device.

In an embodiment of the present invention, the first imaging device is avisible light imaging lens, and the second imaging device is an infraredimaging lens.

In an embodiment of the present invention, the first imaging device isan infrared imaging lens, and the second imaging device is a visiblelight imaging lens.

The present invention further provides a UAV, including a fuselage, anarm connected to the fuselage, a power device configured to provideflight power for the UAV, and the foregoing camera system, the camerasystem being disposed on the fuselage.

Beneficial effects of the present invention are described below: bydisposing the signal trigger device and the signal receiving device, thesignal trigger device generates the trigger signal with the presettrigger frame rate according to the shooting instruction, and the signalreceiving device performs exposure at the preset trigger frame rateaccording to the trigger signal, thereby implementing synchronousexposure and improving shooting quality.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of an unmanned aerial vehicle(UAV) according to an embodiment of the present invention.

FIG. 2 is a schematic structural diagram of a camera system in a UAVaccording to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a first imaging device sending atrigger signal to a second imaging device according to an embodiment ofthe present invention.

FIG. 4 is a schematic diagram of a main processor sending a triggersignal to a first imaging device and a second imaging device accordingto an embodiment of the present invention.

FIG. 5 is a flowchart of a camera imaging method according to anembodiment of the present invention.

FIG. 6 is a schematic diagram of signal synchronization between a firstimaging device and a second imaging device according to an embodiment ofthe present invention.

DETAILED DESCRIPTION

The present invention is further described below with reference to theaccompanying drawings and specific implementations. It should be notedthat, the embodiments or technical features described below may berandomly combined to form new embodiments in case that no conflictoccurs.

As shown in FIG. 1 , a camera imaging method according to an embodimentof the present invention is applied to a camera system of an unmannedaerial vehicle (UAV). The UAV 100 may be a suitable UAV, including afixed-wing UAV and a rotary-wing UAV, such as a helicopter, a quadrotorand an aircraft with other numbers of rotors and/or rotor configuration.The UAV 100 may further be other movable objects, such as a mannedaircraft, a model airplane, an unmanned airship and an unmanned hot airballoon.

In some embodiments, the UAV 100 includes a fuselage 10, an arm 20connected to the fuselage 10, a power device 40 disposed on the arm 20and a camera system 30 disposed on the fuselage 10. The power device 40is configured to provide flight power for the UAV 100. As shown in FIG.2 , the camera system 30 includes a signal trigger device 31 and asignal receiving device 32. The signal trigger device 31 is configuredto acquire a shooting instruction, and generate a trigger signal with apreset trigger frame rate according to the shooting instruction.

The signal receiving device 32 is configured to perform exposure at thepreset trigger frame rate according to the trigger signal. The presettrigger frame rate is greater than a default exposure frame rate of thesignal receiving device.

As shown in FIG. 3 , in an embodiment of the present invention, thesignal trigger device 31 is a first imaging device 310, and the signalreceiving device 32 is a second imaging device 320. The preset triggerframe rate is a default exposure frame rate of the first imaging device310. The default exposure frame rate of the first imaging device 310 isgreater than a default exposure frame rate of the second imaging device320. The first imaging device 310 performs exposure according to thedefault exposure frame rate of the first imaging device, and sends atrigger signal to the second imaging device 320 before exposure. Inother words, the first imaging device 310 performs exposure immediatelyafter sending the trigger signal to the second imaging device 320. Thesecond imaging device 320 performs exposure at the default exposureframe rate of the first imaging device according to the trigger signal,so that the first imaging device 310 and the second imaging device 320implementing synchronous exposure.

As shown in FIG. 4 , in an embodiment of the present invention, thesignal trigger device 31 may be a main processor 311 of the camerasystem 30, and the signal receiving device 32 is a first imaging device321 and a second imaging device 322. The preset trigger frame rate is atrigger frame rate of the main processor 311. The trigger frame rate ofthe main processor 311 is greater than the default exposure frame rateof the first imaging device 321 and the default exposure frame rate ofthe second imaging device 322. A sending time interval between twoadjacent trigger signals of the main processor 311 is smaller than anexposure time interval between two adjacent images when the firstimaging device 321 performs exposure at its default exposure frame rate.A sending time interval between two adjacent trigger signals of the mainprocessor 311 is smaller than an exposure time interval between twoadjacent images when the second imaging device 322 performs exposure atits default exposure frame rate. The first imaging device 321 and thesecond imaging device 322 perform timing after exposure each time andperform exposure after receiving the trigger signal and re-timing. Ifreceiving a trigger signal again when an exposure time corresponding tothe default frame rate is not reached, the first imaging device and thesecond imaging device perform re-timing after the exposure. The rest canbe done in a same manner. Both the first imaging device 321 and thesecond imaging device 322 are adjusted to perform exposure according toa frame rate of the trigger signal. The first imaging device 321 and thesecond imaging device 322 perform exposure at the trigger frame rate ofthe main processor 311 according to the trigger signal, therebyimplementing synchronous exposure of the first imaging device 321 andthe second imaging device 322.

In each of the foregoing embodiments, the first imaging device is avisible light imaging lens, and the second imaging device is an infraredimaging lens. Alternatively, the first imaging device is the infraredimaging lens, and the second imaging device is the visible light imaginglens.

As shown in FIG. 5 , a camera imaging method according to an embodimentof the present invention is performed by the camera system 30 of theforegoing UAV 100, and the method includes:

Step S101: A signal trigger device acquires a shooting instruction.

For example, when a user operates a shooting button on a camera, theshooting instruction is generated.

Step S102: The signal trigger device generates a trigger signal with apreset trigger frame rate according to the shooting instruction.

The signal trigger device may be any of a first imaging device, a secondimaging device, or a main processor. The first imaging device and thesecond imaging device perform exposure independently. The first imagingdevice performs the exposure according to a default exposure frame rateof the first imaging device when receiving no trigger signal. The secondimaging device performs the exposure according to a default exposureframe of the second imaging device when receiving no trigger signal. Thetrigger signal may be sent by the first imaging device to the secondimaging device according to the default exposure frame rate of the firstimaging device. In this case, the preset trigger frame rate is thedefault exposure frame rate of the first imaging device. Alternatively,the second imaging device may send the trigger signal to the firstimaging device according to the default exposure frame rate of thesecond imaging device. In this case, the preset trigger frame rate isthe default exposure frame rate of the second imaging device.Alternatively, the main processor sends the trigger signal to the firstimaging device and the second imaging device according to its triggerframe rate, and the first imaging device or the second imaging deviceperforms the exposure according to a trigger frame rate of the mainprocessor. In this case, the preset trigger frame rate is the triggerframe rate of the main processor.

Step S103: The signal receiving device performs exposure at the presettrigger frame rate according to the trigger signal. The preset triggerframe rate is greater than a default exposure frame rate of the signalreceiving device.

As shown in FIG. 3 , in a first implementation, a signal trigger deviceis a first imaging device, and a signal receiving device is a secondimaging device. A preset trigger frame rate is a default exposure framerate of the first imaging device. A trigger signal is sent by the firstimaging device to the second imaging device according to the defaultexposure frame rate of the first imaging device. The default exposureframe rate of the first imaging device is greater than a defaultexposure frame rate of the second imaging device. An exposure timeinterval between two adjacent images produced by the first imagingdevice through exposure at its default exposure frame rate is smallerthan an exposure time interval between two adjacent images produced bythe second imaging device through exposure at its default exposure framerate. The first imaging device performs exposure at the default exposureframe rate of the first imaging device, and sends a trigger signal tothe second imaging device before exposure. In other words, the firstimaging device performs exposure immediately after sending the triggersignal to the second imaging device. The second imaging device performsexposure at the default exposure frame rate of the first imaging deviceaccording to the trigger signal, so that the first imaging device andthe second imaging device implement synchronous exposure. In anembodiment of the present invention, the method may further include:fusing an image produced by the first imaging device at its defaultexposure frame rate with an image produced by the second imaging devicethrough exposure at the default exposure frame rate of the first imagingdevice to obtain a captured image.

In particular, as shown in FIG. 6 , an exposure time interval betweentwo adjacent images of the first imaging device is t1, and an exposuretime interval between two adjacent images of the second imaging deviceis t2, t2>t1. Timers are disposed in both the first imaging device andthe second imaging device. Re-timing is performed after exposure eachtime to perform a next exposure. When receiving a shooting instruction,the first imaging device performs one exposure after a time t1, and atthe same time sends a trigger signal to the second imaging device. Thesecond imaging device performs one exposure after a time t2 (that is, ata point A). When the trigger signal reaches the second imaging device ata time (that is, at a point B), exposure is performed again. After theexposure ends, timing is performed. After t1 (that is, at a point C),the trigger signal reaches the second imaging device, and the secondimaging device performs exposure, and re-timing is performed after theexposure. Because t2>t1, when the time does not reach t2, the secondimaging device performs the exposure. The rest can be done in a samemanner. The second imaging device is adjusted to perform one exposureevery time t1, so that exposure times of the first imaging device andthe second imaging device are the same, implementing synchronousexposure of the first imaging device and the second imaging device.Images, produced through exposure of each frame of the first imagingdevice and the second imaging device, are fused to obtain a capturedimage of each frame.

In a first implementation, the first imaging device is a visible lightlens, and the second imaging device is an infrared thermal imaging lens.The visible light lens performs exposure at its default frame rate, andat the same time sends a trigger signal to the infrared imaging lens.The infrared imaging lens performs exposure according to the triggersignal.

In another implementation, the first imaging device is an infraredthermal imaging lens, and the second imaging device is a visible lightlens. The infrared thermal imaging lens performs exposure at its owndefault frame rate, and at the same time sends a trigger signal to thevisible light lens. The visible light lens performs exposure accordingto the trigger signal.

As shown in FIG. 4 , in another embodiment of the present invention, asignal trigger device is a main processor, and a signal receiving deviceis a first imaging device and a second imaging device. A trigger signalis sent from the main processor to the first imaging device and thesecond imaging device. A preset trigger frame rate is a trigger framerate of the main processor. The trigger frame rate of the main processoris greater than a default exposure frame rate of the first imagingdevice and a default exposure frame rate of the second imaging device. Asending time interval between two adjacent trigger signals of the mainprocessor is smaller than an exposure time interval between two adjacentimages when the first imaging device performs exposure at its defaultexposure frame rate. A sending time interval between two adjacenttrigger signals of the main processor is smaller than an exposure timeinterval between two adjacent images when the second imaging deviceperforms exposure at its default exposure frame rate. The first imagingdevice and the second imaging device perform timing after exposure eachtime and perform exposure after receiving the trigger signal andre-timing. If receiving a trigger signal again when an exposure timecorresponding to the default frame rate is not reached, the firstimaging device and the second imaging device perform re-timing after theexposure. The rest can be done in a same manner. Both the first imagingdevice and the second imaging device are adjusted to perform exposureaccording to a frame rate of the trigger signal. The first imagingdevice and the second imaging device perform the exposure at the triggerframe rate of the main processor according to the trigger signal,thereby implementing synchronous exposure of the first imaging deviceand the second imaging device. Images generated by the first imagingdevice and the second imaging device through the exposure according tothe trigger frame rate of the main processor are fused to obtain acaptured image.

The first imaging device is a visible light imaging lens, and the secondimaging device is an infrared imaging lens. Alternatively, the firstimaging device is the infrared imaging lens, and the second imagingdevice is the visible light imaging lens.

In an embodiment of the present invention, an image produced by thevisible light lens through exposure is zoomed and then fused with theinfrared imaging lens, to ensure resolution of an output image.

In the foregoing embodiment, through generation of the trigger signal,the exposure frame rate of the first imaging device or the secondimaging device is adjusted, so as to implement synchronous exposure ofthe first imaging device and the second imaging device, and ensuredefinition of an image output by the camera.

It may be learned from description of the foregoing implementationsthat, a person skilled in the art may clearly understand that thepresent invention may be implemented by using software in addition to anecessary universal hardware platform. Based on such an understanding,the technical solutions in the present invention essentially or the partcontributing to the prior art may be implemented in a form of a softwareproduct. The computer software product is stored in a storage medium andincludes several instructions for instructing a computer device (whichmay be a personal computer, a server, a network device, or the like) toperform all or some of the steps of the methods described in theembodiments of the present invention. The foregoing storage mediumincludes: any medium that can store program code, such as a USB flashdrive, a removable hard disk, a read-only memory (ROM), a random accessmemory (RAM), a magnetic disk, or an optical disk.

It should be noted that the sequence numbers of the foregoingembodiments of the present invention are merely for description purposebut do not represent the preference of the embodiments. Moreover, theterms “include”, “comprise”, and any variants thereof in thisspecification are intended to cover a non-exclusive inclusion.Therefore, in the context of a process, an apparatus, an object, or amethod that includes a series of elements, the process, apparatus,object, method or not only includes such elements, but also includesother elements not specified expressly, or may include inherent elementsof the process, apparatus, object, or method. Without more limitations,elements defined by the sentence “including one” does not exclude thatthere are still other same elements in the processes, apparatuses,objects, or methods.

The foregoing implementations are merely exemplary implementations ofthe present invention, and are not intended to limit the protectionscope of the present invention. Any non-substantive changes andreplacement performed by a person skilled in the art based on thepresent invention all belong to the protection scope of the presentinvention.

What is claimed is:
 1. A camera imaging method, applied to a camerasystem, the camera system comprising at least two imaging devices,wherein the method comprises: acquiring, a shooting instruction;generating, a trigger signal with a preset trigger frame rate accordingto the shooting instruction; performing, by the at least two imagingdevices, exposure at the preset trigger frame rate according to thetrigger signal.
 2. The camera imaging method according to claim 1,wherein the method further comprises: performing, by the at least twoimaging devices, timing after exposure each time and perform exposureafter receiving the trigger signal and re-timing; performing, by the atleast two imaging devices, re-timing after the exposure when receiving atrigger signal again when an exposure time corresponding to the defaultframe rate is not reached.
 3. The camera imaging method according toclaim 1, wherein the camera system comprising a first imaging device anda second imaging device, and the preset trigger frame rate being adefault exposure frame rate of the first imaging device, the defaultexposure frame rate of the first imaging device being greater than adefault exposure frame rate of the second imaging device; wherein asending time interval between two adjacent trigger signals is smallerthan an exposure time interval between two adjacent images when thefirst imaging device performs exposure at its default exposure framerate, and the sending time interval between two adjacent trigger signalsis smaller than an exposure time interval between two adjacent imageswhen the second imaging device performs exposure at its default exposureframe rate; and the performing, by the at least two imaging devices,exposure at the preset trigger frame rate according to the triggersignal comprises: performing, by the second imaging device, exposure atthe default exposure frame rate of the first imaging device according tothe trigger signal.
 4. The camera imaging method according to claim 3,wherein the method further comprises: fusing an image produced by thefirst imaging device at its default exposure frame rate with an imageproduced by the second imaging device through exposure at the defaultexposure frame rate of the first imaging device.
 5. The camera imagingmethod according to claim 3, wherein the first imaging device is avisible light imaging lens, and the second imaging device is an infraredimaging lens.
 6. The camera imaging method according to claim 1, whereinthe method further comprises: performing zooming on an image producedthrough exposure of the visible light lens.
 7. A camera system,comprising at least two imaging devices, wherein the one of the at leasttwo imaging devices is configured to acquire a shooting instruction; andgenerate a trigger signal with a preset trigger frame rate according tothe shooting instruction; and the at least two imaging devices isconfigured to perform exposure at the preset trigger frame rateaccording to the trigger signal.
 8. The camera system according to claim7, wherein the at least two imaging devices is further configured to:perform timing after exposure each time and perform exposure afterreceiving the trigger signal and re-timing; and perform re-timing afterthe exposure when receiving a trigger signal again when an exposure timecorresponding to the default frame rate is not reached.
 9. The camerasystem according to claim 7, wherein the at least two imaging devicescomprise a first imaging device and a second imaging device, and thepreset trigger frame rate being a default exposure frame rate of thefirst imaging device, the default exposure frame rate of the firstimaging device being greater than a default exposure frame rate of thesecond imaging device; wherein a sending time interval between twoadjacent trigger signals is smaller than an exposure time intervalbetween two adjacent images when the first imaging device performsexposure at its default exposure frame rate, and the sending timeinterval between two adjacent trigger signals is smaller than anexposure time interval between two adjacent images when the secondimaging device performs exposure at its default exposure frame rate; andthe at least two imaging devices is configured to perform exposure atthe preset trigger frame rate according to the trigger signal comprises:performing, by the second imaging device, exposure at the defaultexposure frame rate of the first imaging device according to the triggersignal.
 10. The camera system according to claim 9, wherein the camerasystem further configured to: fuse an image produced by the firstimaging device at its default exposure frame rate with an image producedby the second imaging device through exposure at the default exposureframe rate of the first imaging device.
 11. The camera system accordingto claim 9, wherein the first imaging device is an infrared imaging lensand the second imaging device is a visible light imaging lens.
 12. Thecamera system according to claim 7, wherein the camera system furtherconfigured to: perform zooming on an image produced through exposure ofthe visible light lens.
 13. An unmanned aerial vehicle (UAV), comprisinga fuselage; an arm connected to the fuselage; a power device configuredto provide flight power for the UAV; and a camera system, the camerasystem being disposed on the fuselage, wherein the camera systemcomprise at least two imaging devices, wherein the one of the at leasttwo imaging devices is configured to acquire a shooting instruction; andgenerate a trigger signal with a preset trigger frame rate according tothe shooting instruction; and the at least two imaging devices isconfigured to perform exposure at the preset trigger frame rateaccording to the trigger signal.
 14. The UAV according to claim 13,wherein the at least two imaging devices is further configured to:perform timing after exposure each time and perform exposure afterreceiving the trigger signal and re-timing; and perform re-timing afterthe exposure when receiving a trigger signal again when an exposure timecorresponding to the default frame rate is not reached.
 15. The UAVaccording to claim 13, wherein the at least two imaging devices comprisea first imaging device and a second imaging device, and the presettrigger frame rate being a default exposure frame rate of the firstimaging device, the default exposure frame rate of the first imagingdevice being greater than a default exposure frame rate of the secondimaging device; wherein a sending time interval between two adjacenttrigger signals is smaller than an exposure time interval between twoadjacent images when the first imaging device performs exposure at itsdefault exposure frame rate, and the sending time interval between twoadjacent trigger signals is smaller than an exposure time intervalbetween two adjacent images when the second imaging device performsexposure at its default exposure frame rate; and the at least twoimaging devices is configured to perform exposure at the preset triggerframe rate according to the trigger signal comprises: performing, by thesecond imaging device, exposure at the default exposure frame rate ofthe first imaging device according to the trigger signal.
 16. The UAVaccording to claim 15, wherein the camera system further configured to:fuse an image produced by the first imaging device at its defaultexposure frame rate with an image produced by the second imaging devicethrough exposure at the default exposure frame rate of the first imagingdevice.
 17. The UAV according to claim 15, wherein the first imagingdevice is an infrared imaging lens and the second imaging device is avisible light imaging lens.
 18. The UAV according to claim 13, whereinthe camera system further configured to: perform zooming on an imageproduced through exposure of the visible light lens.